Phytosterol blends

ABSTRACT

A blend including phytosterol together with saturated fatty acids and/or saturated ratty alcohols is disclosed.

This is a division, of application Ser. No. 584,319, filed June 6, 1975,now U.S. Pat. No. 4,218,334.

The present invention relates to phytosterol blends and moreparticularly to blends including phytosterols together with fatty acidsor fatty alcohols. The present invention also relates to the process ofpreparing such blends.

It has been found that phytosterols can be used advantageously invarious emulsions. The phytosterols serve as auxiliary emulsifiers aswell as modifiers of the consistency and appearance of the emulsion. Thephytosterols act as high slip agents and as conditioning additives. Theterm "Phytosterol" as used herein will mean sterol obtained from plantsources. A difficulty encountered in such utilization of phytosterolsresults from the relatively high melting point of the phytosterols,usually at least 135° C., typically 136°-140° C. If the phytosterol isadded directly to the emulsion, the emulsion and the phytosterol must bemaintained at an elevated temperature over a prolonged mixing time inorder to effect dissolution of the phytosterol. I have now discoveredthat the difficulty of effecting dissolution of the phytosterol can beovercome by blending the phytosterols with either free fatty acids orfree fatty alcohols. The term "phytosterol blend" as used herein willmean a blend of phytosterol and either saturated free fatty acids orsaturated free fatty alcohols.

The phytosterols used in the present invention typically may includestigmasterol, campesterol, sitosterol and/or brassicasterol. Generally,however, the phytosterol in the present invention will be a mixture oftwo or more of such phytosterols. The phytosterols are preferablypresent in the free form. However, in some instances, the phytosterolsmay be in the naturally occurring ester form.

The fatty acid of the present invention is the saturated fatty acidshaving even numbered chain lengths of from 12 to 18 carbon atoms.Typically, lauric acid, myristic acid, palmitic acid and stearic acid.It has been found undesirable to use the unsaturated fatty acids sinceseparation of the phytosterol and such fatty acids will result uponstorage at room temperature. Further, if the unsaturated fatty acids areused, discoloration of the mixture may result.

The saturated fatty alcohols utilized in the present invention includeany of the alcohols having even numbered chain lenghts of from 12 to 18carbon atom members. Saturated fatty alcohols typically include laurylalcohol, myristyl alcohol, cetyl alcohol and stearyl alcohol.

The blend of the present invention typically may include up to 50%,preferably from about 10 to 50 percent phytosterol and at least 50%,preferably from about 50 to 90 percent free saturated fatty acid and/oralcohol, by weight. (The term "percent, parts" and the like as usedherein will refer to "percent, parts" and the like by weight unlessotherwise specified.) The blend of the present invention may be used forany of a variety of purposes including preparation of cosmeticemulsions. The blend of the present invention may be prepared by heatingthe fatty acid or fatty alcohol and dispersing the phytosterol into thefatty acid or fatty alcohol. In order to facilitate more rapiddispersion, the phytosterol may be heated to a molten conditiontypically a temperature of at least about 135° to 140° C. and thephytosterol is dispersed in the melted fatty acid or fatty alcohol. Thefatty acid or fatty alcohol may be at a temperature of at least about45° C., preferably at least 60° C. In any event the temperature of thefatty acid or fatty alcohol is sufficient to melt same, but not so highas to degrade the fatty acid or fatty alcohol. The resulting mixture isthen cooled to room temperature. In certain instances, the presence ofthe phytosterol actually reduces the melting point of the mixture belowthat of the fatty acid or fatty alcohol in its pure form. For example,in one instance in which the blend included 30 percent phytosterol and70 percent stearic acid (Triple Pressed) the melting point of themixture was 54° C. The melting point of the phytosterol was itself 138°C. The melting point of the stearic acid was about 69° C. A mixtureincluding 50 percent phytosterol and 50 percent stearyl alcohol wasfound to have a melting point of approximately 60° C. and the meltingpoint of the pure alcohol was approximately 60° C.

Preferred embodiments of the present invention include a mixture of from10 to 30% phytosterol and from 90 to 70% stearic acid. The mixture issubstantially free of glycerides since the presence of glyceridesmaterially reduce the amount of sterol one may get into the stableblend. If any significant amount of glycerides are present, one isunable to prepare mixtures having 10% or more sterols present. Anothersuch embodiment includes from 10 to 50% phytosterol and from 90 to 50%stearyl alcohol. Of course, various other embodiments come within thescope of the present invention.

EXAMPLE I

A blend was prepared according to the present invention by heating 70parts of stearic acid (Triple Pressed) to a temperature of about 70° C.and dispersing 70 parts of a phytosterol mixture at about 135° C. intothe melted stearic acid. The phytosterol mixture included about 56%sitosterol, 28% campesterol, 4% stigmasterol and 12% other materials.The blend was then cooled to room temperature. A cosmetic emulsion wasprepared by dispersing one part triethanolamine in 94 parts of water.Five parts of the previously prepared phytosterol blend was then added.A control emulsion was likewise prepared including five parts of stearicacid, one part triethanolamine and 94 parts of water. The resultingemulsions were initially similar in appearance. However, the emulsioncontaining the phytosterol blend did not have a soapy characteristicwhereas the control did have such an undesirable characteristic. Also,when the emulsion containing the phytosterol blend was applied to theskin, a smoother feel was noted. The two emulsions were aged forapproximately one week at room temperature. The control remained a thickgel like consistency whereas the emulsion including the phytosterolblend became a flowable fluid thus overcoming the normally undesirablethickening characteristic of triethanolaminesterate emulsions. Thecontrol was translucent and paracrystalline which is typical oftriethanolaminestearate emulsions. The phytosterol emulsion however wasa white emulsion with a pearly sheen. This emulsion, when studied undera microscope, was found to include very fine particles. The phytosterolemulsion was centrifuged and it was found that the very fine particlesremained in emulsion.

EXAMPLE II

A series of blends were prepared to identify the capillary melting pointof stearic acid-phytosterol mixtures. The phytosterol included 56%sitosterol, 28% campesterol, 4% stigmasterol and 12% other materials.The mixtures were prepared as described in Example I. The ratios ofstearic acid-phytosterol were as shown in Table I.

                                      TABLE I                                     __________________________________________________________________________    Sample  A  B C D E F G  H  I  J  K  L                                         __________________________________________________________________________    Phytosterol                                                                            0  5                                                                              10                                                                              20                                                                              30                                                                              40                                                                              50 60 70 80 90 100                                       (percent)                                                                     Stearic Acid*                                                                         100                                                                              95                                                                              90                                                                              80                                                                              70                                                                              60                                                                              50 40 30 20 10  0                                        Melting Point,                                                                        68 56                                                                              56                                                                              55                                                                              54                                                                              73                                                                              101                                                                              101                                                                              112                                                                              119                                                                              127                                                                              136                                       °C.                                                                    __________________________________________________________________________     *Triple Pressed                                                          

A Eutectic mixture is noted between the stearic acid/phytosterol ratiosof 5/95 to 30/70.

EXAMPLE III

Example II was repeated except that the blend was of stearyl alcohol andthe phytosterol mixture. The ratios of stearyl alcohol and phytosterolwas as shown in Table II.

                                      TABLE II                                    __________________________________________________________________________    Sample  A  B C D E F G H  I  J  K  L                                          __________________________________________________________________________    Phytosterol                                                                            0  5                                                                              10                                                                              20                                                                              30                                                                              40                                                                              50                                                                              60 70 80 90 100                                        (percent)                                                                     Steryl Alcohol                                                                        100                                                                              95                                                                              90                                                                              80                                                                              70                                                                              60                                                                              50                                                                              40 30 20 10  0                                         Melting Point,                                                                        59 58                                                                              58                                                                              57                                                                              59                                                                              59                                                                              59                                                                              101                                                                              111                                                                              117                                                                              123                                                                              136                                        °C.                                                                    __________________________________________________________________________

A substantially reduced melting point is maintained through a 50:50mixture of stearyl alcohol and phytosterol.

EXAMPLE IV

A blend including iso-stearic acid and phytosterol was prepared byheating 90 parts ios-steric acid (Emery 875-D Isosteric Acid™) to 80° C.and then blending in 10 parts of phytosterol. The mixture was cooled toroom temperature. A stable clear liquid was obtained.

EXAMPLE V

A blend was prepared as described in Example IV except the iso-stearicacid was replaced with iso-stearyl alcohol. Similar results wereobtained.

EXAMPLE VI

A shampoo was prepared incorporating the present fatty acid andphytosterol. 450 parts of iso-stearic acid were heated in a stainlesssteel container to a temperature of 70° C. Phytosterol in an amount of50 parts was added with stirring. A clear solution was obtained. Thesolution was cooled to room temperature. A shampoo having the followingcomposition was prepared.

                  TABLE III                                                       ______________________________________                                                          %    Grams                                                  ______________________________________                                        Sodium lauryl sulfate                                                                             62.8   628                                                (30% aqueous solution)                                                        Phytosterol - fatty 3.3    33                                                 acid blend                                                                    Triethanolamine lauryl                                                                            4.6    46                                                 sulfate (40% solution)                                                        KOH Solution 34%    1.0    10                                                 Mixture of lauric and                                                                             1.5    15                                                 myristic diethanolamides                                                      (Clindrol 100 LM™ )                                                        Water               26.8   268                                                                           1000                                               ______________________________________                                    

The water was placed in a vessel and heated to 70° C. The KOH solutionwas added with mixing. The phytosterol fatty acid was mixed in. Thesodium lauryl sulfate solution was added and the temperature was raisedto 85° C. and maintained between 80° and 85° C. for about 20 minutes andthen cooled to 55° C. The mixture of lauric and myristic diethanolamideswas added and mixed until dissolved. The resulting mixture was cooled toroom temperature and sufficient water was added to bring the finalweight to 1000 grams. This was to compensate for the water that waslost. A portion (96 grams) of the resulting shampoo was placed in abeaker and 4 grams of glycerol was added. The mixture was heated toabove 80° C. and stirred for five minutes. The resulting mixture wasused to wash hair tresses.

EXAMPLE VII

A blend was prepared according to the present invention by heating 70parts reagent grade lauric acid to about 45° C. and adding thereto thephytosterol mixture described in Example I. The phytosterol mixture wasat 135° C. The blend was stirred until it became viscous and thenallowed to remain undisturbed until solidification took place. Themelting point of the blend was found to be about 50° C.

EXAMPLE VIII

A blend was prepared as described in Example VII except the reagentgrade lauric acid was replaced with cosmetic grade lauric acid (Neo-Fat12™ produced by Armak). The results were similar except the meltingpoint of the blend was found to be about 56° C.

EXAMPLE IX

A blend was prepared by adding 7 parts reagent grade myristic acid and 3parts of the previously described phytosterol mixture to a beaker. Thebeaker was heated until the ingredients melted. The blend was allowed tocool with stirring until it became viscous. The blend then remainedundisturbed until it solidified. The blend had a melting point of about57° C.

EXAMPLE X

Example IX was repeated using palmitic acid. The blend had a meltingpoint of about 67° C.

EXAMPLE XI

A blend was prepared according to the present invention by placing 7parts dodecyl alcohol and 3 parts phytosterol (primarily sitosterol) ina beaker and heating until the materials melted. The blend was thencooled with stirring until it became viscous. It was then allowed tosolidify. The resulting blend had a melting point of about 30° C.

EXAMPLE XII

Example XI was repeated, however, using cetyl alcohol. The resultingblend had a melting point of about 50° C.

EXAMPLE XIII

Example XI was repeated using instead myristyl alcohol. The resultingblend had a melting point of about 62° C.

EXAMPLE XIV

A comparison was made of the ease of incorporating the present blendinto mineral oil in relation to the ease of incorporating the separateingredients. A blend was prepared including 23 grams stearic acid and 10grams phytosterol. The phytosterol was a mixture including 56%sitosterol, 28% campesterol and 4% stigmasterol (sold by General MillsChemicals, Inc. under the trademark Generol 122). The stearic acid andphytosterol were placed in a beaker and heated to 110° C. with mixinguntil they were clear. The mixture was cooled to 80° C. and poured in athin layer onto a sheet of aluminum foil to cool. After reaching roomtemperature, the blend was broken up into flakes. Sixty seven grams ofmineral oil were placed in each of two beakers (A and B). Beakers A andB containing the mineral oil were then each heated to and held at 80° C.Thirty three grams of the blend were added to the mineral oil in beakerA with constant agitation until the solution became clear which required40 seconds. Ten grams of the phytosterol and 23 grams of the stearicacid were added to the mineral oil in beaker B with constant agitationuntil the solution became clear. This required 240 seconds. The use ofthe present blend was found to have substantial advantage over additionof the separate materials.

EXAMPLE XV

Example XIV was repeated except the stearic acid was replaced withstearyl alcohol. The blend dissolved in the mineral oil in 50 seconds;whereas the separate stearyl alcohol and phytosterol alcohol required180 seconds to form the clear solution.

I claim:
 1. A blend consisting essentially of from about 10 to 50percent phytosterol and from about 50 to 90 percent of a member selectedfrom the group consisting of free saturated fatty alcohols having aneven number of carbon atoms from 12 to 18 in number, said blend beingsubstantially free of triglyceride.
 2. The blend of claim 1 wherein saidalcohol is stearyl alcohol.
 3. The blend of claim 1 wherein the fattyalcohol is lauryl alcohol.
 4. The blend of claim 1 wherein the fattyalcohol is myristyl alcohol.
 5. The blend of claim 1 wherein the fattyalcohol is cetyl alcohol.